Growth and cytodifferentiation of the fetal lamb adrenal cortex prior to parturition.
Growth and cytodifferentiation of the fetal lamb adrenal cortex prior to parturition.
复制标题
分娩前胎儿羔羊肾上腺皮质的生长和细胞分化。
作者：
D. Boshier;H. Holloway;G. Liggins
本文研究了从妊娠136天到正常出生的胎羊肾上腺皮质的生长规律和细胞分化。在此期间，腺体的重量几乎翻了一番（0.45- 0.80 g），内皮质区（束状皮质+网状皮质）的厚度几乎增加了四倍（0.33- 1.25 mm）。136天后开始进入快速增长阶段，增长模式基本上是线性的。内皮层区由明细胞和暗细胞组成，明细胞的数量比暗细胞的数量成比例增加。这种细胞比例的变化与胎儿皮质醇的增加有关。随着生长和分化的进行，浅色细胞越来越多地具有更多的囊泡状SER;正统配置的线粒体，主要是囊泡状嵴;发育良好的高尔基复合体，具有许多小的，刷毛涂层的囊泡;和高尔基复合体附近的深色颗粒，在外周细胞质中，和细胞外部。内皮质区体积增加了6倍，细胞分化的超微结构证据似乎足以解释在妊娠的这个阶段胎儿皮质醇合成增加的已知原因。
Growth patterns and cytodifferentiation of the fetal lamb adrenal cortex, from 136 days of gestation to birth at normal term, have been examined. The gland almost doubles in weight over this period (0.45--0.80 g) and the inner cortical zone (zona fasciculata+zona reticularis) nearly quadruples in thickness (0.33--1.25 mm). The phase of rapid growth has begun by 136 days, and the growth patterns are essentially linear. The inner cortical zone consists of light and dark cells, the former increasing in number proportionately more than the dark cells. This change in the cell ratio is linked with increased fetal production of cortisol. As growth and differentiation proceed the light cells increasingly possess a more vesicular SER; mitochondria of the orthodox configuration, with predominantly vesicular cristae; a well developed Golgi complex with numerous small, bristle coated vesicles; and dark granules near the Golgi complex, in the peripheral cytoplasm, and external to the cells. The sixfold increase in the volume of the inner cortical zone and the ultrastructural evidence of cytodifferentiation appear adequate to account for the known increase in the fetal synthesis of cortisol during this stage of pregnancy.